Naslov
Effect of electrical potential on adhesion, spreading and detachment of organic droplets at aqueous metallic interface

Autori
Ivošević, Nadica ; Žutić, Vera

Vrsta, podvrsta i kategorija rada
Poglavlja u knjigama, znanstveni

Knjiga
Contact angle, wettability and adhesion

Urednik/ci
Mittal, Kash L.

Izdavač
CRC Press

Godina
2002

Raspon stranica
549-561

ISBN
978-90-6764-370-2

Ključne riječi
adhesion at mercury electrode, droplet detachment, dropping mercury electrode, electrical adhesion signals, hydrocarbon droplets, wetting transients

Sažetak
We demonstrate how spreading and shape of organic droplets at the fluid interface mercury/aqueous electrolyte depend on the interfacial tension that is controlled by the applied potential. We indicate a method to characterize of wetting transients of organic liquids by recording electrical signals of organic microdroplets at the dropping mercury electrode. Electrical signals are fast current transients. The flow of current is caused by double-layer charge displacement due to adhesion and spreading of a single microdroplets. Spike-shaped electrical signals are characterized by maximum current in � ÝA range, duration in ms time scale and displaced charge in nC range. The adhesion and spreading of droplets are enhanced by the hydrodynamic regime of the electrode growing, fluid interface. This technique thus allows precise measurement of area of contact interface assuming validity of the electrical double-layer model. Adhesion of macroscopic hexadecane droplet at stationary mercury electrode leads to immediate formation of an underlying monolayer and to a high over-potential (-700 mV) for droplet detachment. The wetting phenomena identified in these systems apply more generally for the droplets and insoluble films on solid electrodes and the findings can be extrapolated to complex electrochemical systems of technological importance.

Izvorni jezik
Engleski

Znanstvena područja
Geologija, Kemija

POVEZANOST RADA